Re: [PATCH v2 1/2] perf expr: Add d_ratio operation

Arnaldo Carvalho de Melo
2020-06-11T13:09:42Z

Em Thu, Jun 11, 2020 at 10:38:46AM +0200, Jiri Olsa escreveu:
> On Wed, Jun 10, 2020 at 04:58:22PM -0700, Ian Rogers wrote:
> > d_ratio avoids division by 0 yielding infinity, such as when a counter
> > doesn't get scheduled. An example usage is:
> >
> > {
> > "BriefDescription": "DCache L1 misses",
> > "MetricExpr": "d_ratio(MEM_LOAD_RETIRED.L1_MISS, MEM_LOAD_RETIRED.L1_HIT + MEM_LOAD_RETIRED.L1_MISS + MEM_LOAD_RETIRED.FB_HIT)",
> > "MetricGroup": "DCache;DCache_L1",
> > "MetricName": "DCache_L1_Miss",
> > "ScaleUnit": "100%",
> > }
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
>
> Acked-by: Jiri Olsa <jolsa@redhat.com>

Thanks, applied both,

- Arnaldo

> thanks,
> jirka
>
> > ---
> > tools/perf/tests/expr.c | 2 ++
> > tools/perf/util/expr.l | 1 +
> > tools/perf/util/expr.y | 14 ++++++++++++--
> > 3 files changed, 15 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
> > index 1cb02ca2b15f..c4877b36ab58 100644
> > --- a/tools/perf/tests/expr.c
> > +++ b/tools/perf/tests/expr.c
> > @@ -39,6 +39,8 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
> > ret |= test(&ctx, "1+1 if 3*4 else 0", 2);
> > ret |= test(&ctx, "1.1 + 2.1", 3.2);
> > ret |= test(&ctx, ".1 + 2.", 2.1);
> > + ret |= test(&ctx, "d_ratio(1, 2)", 0.5);
> > + ret |= test(&ctx, "d_ratio(2.5, 0)", 0);
> >
> > if (ret)
> > return ret;
> > diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
> > index f397bf8b1a48..298d86660a96 100644
> > --- a/tools/perf/util/expr.l
> > +++ b/tools/perf/util/expr.l
> > @@ -100,6 +100,7 @@ symbol ({spec}|{sym})+
> > }
> > }
> >
> > +d_ratio { return D_RATIO; }
> > max { return MAX; }
> > min { return MIN; }
> > if { return IF; }
> > diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y
> > index bf3e898e3055..fe145344bb39 100644
> > --- a/tools/perf/util/expr.y
> > +++ b/tools/perf/util/expr.y
> > @@ -10,6 +10,14 @@
> > #include "smt.h"
> > #include <string.h>
> >
> > +static double d_ratio(double val0, double val1)
> > +{
> > + if (val1 == 0) {
> > + return 0;
> > + }
> > + return val0 / val1;
> > +}
> > +
> > %}
> >
> > %define api.pure full
> > @@ -28,7 +36,7 @@
> > %token <num> NUMBER
> > %token <str> ID
> > %destructor { free ($$); } <str>
> > -%token MIN MAX IF ELSE SMT_ON
> > +%token MIN MAX IF ELSE SMT_ON D_RATIO
> > %left MIN MAX IF
> > %left '|'
> > %left '^'
> > @@ -64,7 +72,8 @@ other: ID
> > }
> > |
> > MIN | MAX | IF | ELSE | SMT_ON | NUMBER | '|' | '^' | '&' | '-' | '+' | '*' | '/' | '%' | '(' | ')' | ','
> > -
> > +|
> > +D_RATIO
> >
> > all_expr: if_expr { *final_val = $1; }
> > ;
> > @@ -105,6 +114,7 @@ expr: NUMBER
> > | MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; }
> > | MAX '(' expr ',' expr ')' { $$ = $3 > $5 ? $3 : $5; }
> > | SMT_ON { $$ = smt_on() > 0; }
> > + | D_RATIO '(' expr ',' expr ')' { $$ = d_ratio($3,$5); }
> > ;
> >
> > %%
> > --
> > 2.27.0.278.ge193c7cf3a9-goog
> >
>

--

- Arnaldo